Duplex Stirling coolers are external heat-driven regenerative machines that obtain cooling power with high efficiency and reliability. Although the technology is promising, little progress has been reported since they were invented. This paper examines the influence of system parameters on the cooling performance of a duplex Stirling cooler. The study showed that the system was sensitive to a number of parameters, as slight changes in these parameters resulted in the cooling performance deviating significantly from the design. In practice, deviation of system parameters from the design is inevitable. Therefore, actual systems often produce unexpected performance, and this is likely the main obstacle to utilizing such a system in practical applications. To overcome this disadvantage, two methods were proposed to allow the power piston to move with a constant displacement, which may alloW for duplex Stirling coolers to become a more widely used cooling system. A new configuration for duplex Stirling coolers was also considered, and it showed similar characteristics as the typical configuration. (C) 2017 Elsevier Ltd. All rights reserved.